1. Field of the Invention
The present invention relates to the field of transmission filters and the manufacture thereof. In particular, the invention is concerned with a preferred transmission filter having a first flange transparent to a laser beam and a second flange opaque to the laser beam and meltable upon exposure thereto. The flanges are in registered, abutting relationship with a laser weld bead at the juncture between the flanges to provide a fluid seal circumscribing the filter.
2. Description of the Prior Art
A prior art fluid filter, such as an oil or transmission filter for a vehicle, includes first and second housing sections each presenting a circumscribing flange composed of synthetic resin material with the housing sections defining a chamber containing filter media. One of the flanges presents an upstanding weld rib that engages the surface of the other flange at a juncture. To join the flanges during manufacture, the flanges are vibration welded by vibrating one of the flanges at a high frequency. This creates heat at the juncture to create a weld bead circumscribing the filter and providing a fluid seal. The edges of the filter media are crimped between the flanges inboard of the weld bead to provide an additional fluid seal.
One of the problems with the prior art is that the edges of the filter media cannot be crimped as tightly as desired because to do so might result in damage to the edges during the vibration welding process. Another problem is that vibration welding process may not allow production rates as high as desired.